Final Exam - Multiple Choice

If a two-factor analysis of variance produces a statistically significant interaction, then you can conclude that...

the significance of the main effects is NOT related to the significance of the interaction.

The average verbal SAT score for the entire class of entering freshmen is 530. However, if you select a sample of 20 freshmen and compute their average verbal SAT score you probably will not get exactly 530. What statistical concept is used to explain the natural difference that exists between a sample mean and the corresponding population mean?

Sampling Error

What is the mean for the following sample of scores?

Scores: 1, 2, 5, 4

M = 3

A positive value for a correlation indicates...

increases in X tend to be accompanied by increases in Y.

As the sample size gets larger, the size of the correlation necessary for significance...

the sample means for all the possible samples (for the specific sample size)

What is the value of (ΣX)² for the follwing scores?

Scores: 3, 0, 5, 2

Statistical methods that use sample data to answer general questions about a population are called...

The value of the Pearson Correlation will be negative if...

A researcher measures personality for a sample of n = 50 people and classifies each person as either Type A, Type B, or Type C personality. Which measure of central tendency would be appropriate to summarize these measurements?

In analysis of variance, the F-ratio is a ratio of...

On an exam with a mean of μ = 70, you have a score of X = 65. Which of the following values for the standard deviation would you give the highest position within the class?

What is the median for the following set of scores?

Scores: 1, 2, 5, 6, 17

For a negatively skewed distribution with a mode of X = 25 and a median of 20, the mean is probably...

A researcher is conducting an experiment to evaluate a treatment that is expected to increase the scores for individuals in a population which is known to have a mean of μ = 80. The results will be examined using a one-tailed hypothesis test. Which of the following is the correct statement of the null hypothesis?

Suppose the correlation between height and weight for adults is +0.80. What proportion (or percent) of the variability in weight can be explained by the relationship with height?

In general the distribution of F-ratios is...

For an experiment comparing more than 2 treatment conditions you should use analysis of variance rather than separate t-tests because...

A population has μ = 50 and σ = 5. If 10 points are added to every scoer in the population, then what are the new values for the new mean and standard deviation?

Even if a treatment has an effect it is still possible to obtain an extreme sample mean that is not very different from the original population mean. If this happens, you are likely to...

For a population with μ = 80 and σ = 10, what is the z-score corresponding to X = 95?

The symbol for SS stands for...

In analysis of variance, each independent variable is referred to as a...

The Pearson Correlation measures...

A population with μ = 85 and σ = 12 is transformed into z-scores. After the transformation, the population of z-scores will have a standard deviation of...

A researcher conducts an experiment comparing two treatment conditions and obtains 30 scores in each treatment. Which design would require the smallest number of participants?

In a normal distribution...

As a sample size increases...

For a distribution of scores, which of the following z-score values represents the location closest to the mean?

Which of the following describes the typical chi-square distribution?

Under what circumstances are post hoc tests necessary?

A sample of n = 5 scores has M = 20 and s² = 4. What is the sample standard deviation?

In analysis of variance, the term factor refers to...

A sample of n = 25 individuals is selected from a population with μ = 80 and a treatment is administered to the sample. If the treatment has no effect, then...

A negative value for a correlation indicates...

If the results of a two-factor experiment are presented in a line graph, then an interaction can be seen whenever...

In analysis of variance, MS provides a measure of...

The analysis of variance for a two-factor experiment produces...

For any distribution, what is the z-score corresponding to the mean?

When comparing more than two treatment means, why should you use an analysis of variance instead of using several t-tests?

A population of N = 10 scores has a mean of μ = 80. If 5 points are added to every score in the distribution, what is the value of the new mean?

A z-score of z = -2.00 indicates a position in a distribution...

Which set of test scores has the smallest standard deviation?

A. 11, 17, 31, 53

B. 5, 11, 42, 22

C. 145, 143, 145, 147

D. 27, 105, 10, 80

The numerical value for a correlation...

The results from a two-factor analysis of variance show a significant main effect for factor A and a significant main effect for factor B. Based on this information, you can conclude that...

A two-factor experimental study means that the study has...

A college professor reports that students who finish exams early tend to get better grades than students who hold on to exams until the last possible moment. The correlation between exam score and amount of time spent on the exam is an example of...

For which of the following situations would a repeated-measures research design be appropriate?

A. Comparing verbal skills for girls vs. boys at age 3

B. Comparing pain tolerance before and after taking a new pain medication

C. Comparing self-esteem for students who participate in school athletics vs. those who do not

If other factors are held constant, the standard error of M will _____ as the sample size increases.

A two-factor experiment means that the experiment design includes...

The purpose for the post hoc tests is...

A two-factor study with 2 levels of factor A and 3 levels of factor B uses a separate group of n = 5 participants in each treatment condition. How many participants are needed for the entire study?

For an extremely skewed distribution of scores, the best measure of central tendency would be...

Real limits are an important consideration when measuring a ______ variable.

Which of the following Pearson Correlations shows the greatest strength or consistency of relationship?

A. -0.90

B. +0.74

C. +0.85

D. -0.33

Which of the following symbols identifies the sample standard deviation?

For which of the following situations would a repeated-measures design have the maximum advantage over an independent-measures design?

In a two-factor analysis of variance, a main effect is defined as...

A sample of n = 20 scores is transformed into z-scores. The mean for the 20 z-scores is...

By selecting a smaller alpha level, a reasearcher is...

A professor recorded the academic major for each student in an introductory psychology class. If the data are presented in a frequency distribution graph, what type of graph should be used?

An analysis of variance comparing three treatment conditions produces dftotal = 24. For this ANOVA, what is the value of dfbetween?

What does it mean to obtain a negative value for the chi-square statistic?

Scores from a statistics exam are reported as deviations scores. Which of the following deviation scores indicates a higher position in the class distribution?

A. +8

B. 0

C. -8

D. cannot determine without more information

A researcher conducts an experiment to determine whether moderate doses of St. John's Wort have any effect on memory for college students. For this study, what is the independent variable?

The results from a research study indicate that adolescents who watch more violent content on television also tend to engage in more violent behavior than their peers. The correlation between amount of TV violent content and amount of violent behavior is an example of...

A researcher is curious about the average level of science knowledge for high school seniors in the United States. The entire group of high school students in the U.S.A. is an example of...

If the null hypothesis is true and there is no treatment effect, what value is expected on average for the F-ratio?

The z-score boundaries for the critical region are determined by...

Although a research study is typically conducted with a relatively small group of participants known as a __________, most researchers hope to generalize their results to a much larger group known as a __________.

In an experiment, the researcher manipulates the _______ and measures changes in the ________.

In a two-factor ANOVA, what is the implication of a significant A x B interaction?

How many separate samples would be needed for a two-factor, independent-measures research study with 2 levels of factor A and 3 levels of factor B?

In an experiment, the researcher manipulates the _______ and measures changes in the ________.

In a two-factor ANOVA, what is the implication of a significant A x B interaction?

How many separate samples would be needed for a two-factor, independent-measures research study with 2 levels of factor A and 3 levels of factor B?

In a frequency distribution graph, frequencies are presented on the ______ and the scores (categories) are listed on the ________.